Friction shock-absorbing mechanism



Aug. 28, 1928. 7 1,682,020

J. F. OCONNOR FRICTION SHOCK ABSORBING MECHANISM Filed March 12, 1927 2 Sheets-Sheet 1 a? I D Aug. 28, 1928.

J. F. OCONNOR FRICTION snocx ABSORBING mncmmzsu Filed March 12. 1927 2 Sheets-Sheet 2 a W y Patented Aug. 28, 1928.

UNITED STATES ra'rsnr OFFICE.

JOHN F. OCONNOR, OF CHICAGO, ILLINOIS, ASSIGNOR TO W. H. MINER, INC., 0]? CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE.

FRICTION SHOOK--ABSOBBING MECHANISM.

Application filed March 12, 1927. Serial No. 174,730.

This invention relates to improvements in friction shock absorbing mechanisms.

One object of the invention is to provide a friction shock absorbing mechanism especially adapted for railway draft riggings, including a spring cage provided. with detachable liners at one end forming a friction shell section, friction means co-operating with the liners, a wedge acting member for placing the parts under lateral pressure for holding the liners locked to the shell, together with twin spring means within the shell co-operating with the friction means, wherein the wedge means is anchored to the shell by means integral therewith having engagement with the liners.

Another object. of the invention is to provide a friction shock absorbing mechanism, including a casing having detachable liners at one end thereof with which co-operatc friction shoes, which are held against outward. movement by a wedge having integral means for anchoring the same to the shell by engagement thereof with the inner ends of the liners, the liners being held anchored to the shell by lateral outward pressure of the shoes induced through the action of main spring resistance which is under initial compression, engaging the shoes and holding the latter against the wec e, wherein means is provided for facilitating the assembly of the parts, including detachable face plates interposed between the shoes and wedge.

Other objects and advantages of the invention will more fully and clearly appear from the description and claims hereinafter following.

In the drawings, forming a part of this specification, Figure 1 is a horizontal longitudinal sectional view of a railway draft rigging, showing one embodiment of my im provements in connection therewith. F gure. 2 is a front end elevational view of the shoclr absorbing mechanism proper illustrated in Figure 1. Figure 3 is a vertical transverse sectional view corresponding substantially to the line 33 of Figure 1. Figure & is a longitudinal vertical sectional view of the front end portion of the shock absorbing mechanism illustrated inFignre 1 and corresponding substantially to the line 4-4 of said figure. Figure 5 is a detailed perspective view of one of the face plates employed in connection with the improved shock absorbing mechanism illustrated. in Figures 1 to 4:, inclusive. Figure 6 is a front elevational view of the shock absorbing mechanism proper illustrating another embodiment of invention. And Figure 7 is a horizontal sectional view corresponding substantially to the line 77 of Figure 6.

Referring first to the embodiment of the invention illustrated in Figures 1 to 5, inclusive, 10-1O indicate channelshaped center or draft sills of a railway car under- .frame, to the inner sides of which are secured the usual front stop lugs 1111 and rear stop lugs 1212. The inner end of the drawbar is designated by 13, to which is operatively connected a hooded yoke 14 of well known form.

My improved shock absorbing mechanism proper and a main follower 15 are disposed within the yoke. The yoke and the parts therewithin are supported in operative position by a detachable saddle plate 16 fixed to the draft sills.

The improved shock absorbing mechanism illustrated in Figures 1 to 5, inclusive, comprises broadly: A casing A, a pair of liners B-B; a wedge block C; a pair of friction shoes D and Fqa pair of face plates F-F for the shoes; a spring follower G; and a spring resistance H.

The casing A is in the form of a substantially rectangular box-like casting hav ing longitudinally extending vertical spaced side walls 17-17 horizontally disposed longitudinally extending spaced top and bottom walls 1818 and a vertical end wall 19. The end wall 19 co-operates with the stop lugs 12 in the manner of the usual rear follower. r-lt the forward end, the side walls of the casing A are thickened. as indicated at 2020. The thickened portions of the side walls 20 are each provided with a pair of spaced recesses or'grooves 2l.21 adapted to receive the corresponding projections on the liners to lock the liners against longitudinal movement with respect to the cage.

The liners B are two in number and are disposed at opposite sides of the mechanism. Each liner is provided with a pair of spaced ribs 22 on the outer side thereof adapted to seat in the grooves 21 of the thickened poris 20 of the side walls 17 of the casing A. On the inner side, each liner is provided with a longitudinally extending flat friction surface 23. The surfaces 23 of the two liners preferably converge inwardly of the mechanism and define the friction shell section of the casing A. The portion of the casing A rearwardly of the friction shell section functions as a spring cage.-

The wedge member C is in the form of a block having a flat front .end face 24 hearing on the inner side of the main follower 1.5. At the inner end, the block C is provided with a pair of inwardly converging flat wedge faces on the opposite sides thereof, one of the wedge faces being designated by and the other by 26. The wedl'e face 25 is preferably disposed at a relatively keen wedge acting angle with respect to the longitudinal axis of the mechanism while the wedge face 26 disposed at a relatively blunt releasing angle with respect to said axis. The wedge is cut away at opposite sides indicated at 2727, for a purpose hereinafter described. The cut away sections 27 at the opposite sides of the wedge are in the form of concave recesses.

The friction shoes D and E are disposed at opposite sides of the mechanism and are interposed between the wedge C and the liners B. The two shoes are of similar design except as hereinafter pointed out. Each shoe is provided with a flat outer longitudinally disposed friction surface 28 adapted to co operate with the friction surface 23 of the corresponding liner B. On the inner side, each shoe is laterally enlarged as indicated at 29, the enlargement being;- of cylindrical section as indicated at 127 to interfit with the concave opening or recess 27 at the corresponding side of the wedge. The enlargement 29 of each shoe is provided with a flat front face on the inner side thereof adapted to form a seat for one of the face plates F. The flat outer face of the shoe D is designated by 30 and that of the shoe E is designated by 31. The face 30 of the shoe D is v disposed parallel to the face 25 of the wedge hloclr C and the face 31 of the shoe E is disposed parallel to the face 26 of said wedge block. At their inner ends, the shoes D and E are cut away as indicated at 3232 in Figure 3 to accommodate the outer sides of the inner coils of the twin arranged main spring resistance elements. as most clearly shown in Figure 1, each of the shoes D and E is provided with a flat front end face 33. and the rear end of the enlargement thereof presents a transverse flat abutment face 34. Each shoe is also provided with a central rib 35 projecting from the wedge face thereof. The rib 35 presents a flat front end face 36 which is flush with the front end face 33 of the shoe.

The fa e plates F as most clearly shown in Figure 5, each comprise a central section 37 and short angular sections 38 and 39 at the front and rear ends thereof respectively.

The end sections 38 and 39 and thecentral section 37 all present inner flat faces adapted to bear directly on the corresponding shoe, the section 38 of each plate bearing on the front end face 33 of the shoe and the central section 37 hearing on the wedge face of the shoe. The central section of the plate F which (go-operates with the shoe D is disposed at a keener angle than the central section'37 of the other face plate F which co-operates with the shoe E so that the two face plates F will snugly fit the two shoes D and E. As shown in Figure 5, each face plate F is centrally slotted as indicated at 40 to receive the rib 35 of the corresponding shoe. The face plates present outer wedge faces 41 at their central sections which co-operate with the wedge faces 25 and 26 of the wedge block 0, the faces of the two plates being inclined'to correspond respectively with the inclination of the two wedge faces 25 and 26 of the wedge block C. i

The spring follower Grcomprises a main plate-like section having forwardly projecting arms 42-42 which are adapted to engage the inner ends of the friction shoes. The arms 42 are arranged in top and bottom pairs at opposite sides of the spring follower. The plate-like body portion of the spring); follower G is provided with a pair of spaced openings 43 adapted to loosely ac commodate the front end sections of the innor coils of the main spring resistance elements H.

The wedge block C is provided with means rigid therewith for anchoring the same to the casing A. This anchoring means comprises top and bottom spaced arms in the form of flat plate-like members 44, rearwardly extending therefrom and connected by a transverse end section 43 also of plate-like form, and of such a width as to engage behind the liners B, thereby limitingoutward movement of the wedge block B, but permitting of inward move ment of the same. The plate-like transyerse section 45 of the retaining means is provided with a vertically disposer. central reinforcing rib 46 at the forward side thereof and is also provided with a pair of spaced openings 47 at'opposite sides aligned with the openings 43 of the spring follower G and also adapted to accommodate the front enc sections of the inner coils of the main spring resistance H.

The main spring resistance H comprises twin arranged sets of spring coils, each set comprising an inner relatively light coil 48 and a relatively heavier outer coil 49. The outer coil 49 of each spring has its opposite ends bearing respectively on the spring follower G a the nd l 19 o the cage o casing A. The inner coils 4 8 have their front ends bearing on the transverse end rze faces 34 of the enlargements of the shoes and the rear ends bearing on the end wall 19 of the casing A.

In the assembled condition of the mechanism, the main spring resistance comprising twin arranged sets, is under initial compression, thereby maintaining the shoes in en- "agement with the wedge C and holding the liners anchored to the cage A by the lateral outward pressure exerted through the medium of the shoes. Due to the initial compression under which the spring resistance means is placed, there is a tendency for the shoes to be urged outwardly, thus compensating for wear of the various friction and wedge faces of the mechanism. In order to permit for the expansion of the outer coils of the spring resistance means to compensate for wear, clearance is left between the re taining means on the wedge and the spring follower G. i

In assembling the mechanism, the main spring resistance H, the spring follower G, and the wedge block C are first inserted within the casing A. Then pressure is ap plied to the wedge, forcing the parts in wardly so as to permit insertion of the liners B, and engagement of the ribs 22 within the recesses 21 of the side walls 17 of the casing. The parts are then permitted to expand and the shoes inserted bet-ween the wedge and liners. Then pressure is again applied, this time directly to the shoes by engagement of the ribs thereof by pressure bars. The shoes are forced inwardly a sufhcient distance to permit insertion of the face plates F between the shoes and the wedge block C. It will be noted that the slotted sections of the face plates F will permit the same to engage over the pressure bars. After the face plates F have been put in position, pressure is removed and the parts permitted to expand, assuming the normal position illnstrated in Figure 1. When the parts are in the position shdwn in Figure 1, outward movement of the wedge C is positively limited by the anchoring means thereof, the plate-like section L5 of which engages the inner ends of the liners B. Outward movement of the friction shoes is limited by engagement of the face plates F thereof with the wedge faces of the wedge block C and as the shoes are held outwardly by the spring resistance elements H which are under initial compression, a slight spreading action is produced, thereby holding the shoes apart and maintaining the liners B under lateral pressure and holding the same anchored to the casing A.

The operation of my improved shock absorbing mechanism as illustrated in Figures 1 to 5, inclusive, assuming a compression stroke, is as follows: The spring cage A and main follower 15 will be moved relatively toward each other, thereby forcing the wedge inwardly of the spring cage and setting up a wedging action between'the same and the friction shoes D and E, at the same time forcing the shoes inwardly of the mechanism against the resistance of the main sn'ing H. Due to the lateral outward pressure, the shoes w'll maintain the liners in anchored relation with respect to the cage A. During the relative approach of the cage A and main follower 15, the shoes will be forced inwardly on the friction surfaces of the liners, thereby producing relatively high frictional resistance. This action will continue either until the actuating force is reduced or movement of the main follower is arrested by engagement with the front end of the cage A, whereupon the actuating force will be transmitted, directly through the cage, the latter acting as a solid column load transmitting member to prevent the main spring resistance H from being unduly compressed. In release, when the actuating force is reduced, the expansive action of the main spring resistance H will force the shoes outwardly of the cage A, carrying the wedge C therewith. Outward movement of the wedge will finally be limited by engagemen v of the anchoring means thereof with the inner ends of the liners B, thereb also limiting outward movement of the friction shoes which have wedging' engagement with the block C by means of the face plates F.

It will be evident that by the employn'lent of the detachable face plates, and forming the friction shoes and wedge block so that the shoes may be inserted after the liners have been placed in position, and then add ing the detachable face plates, assemblage of the mechanism is greatly facilitated and simplified.

Referring next to the embodiment of the invention illustrated in Figures 6 and 7, the same comprises broadly: A casing A provided with a pair of liners BB; a wedge member C; a pair of friction shoes DE a pair of face plates FF; a main spring follower G; and a main spring resistance H.

The spring cage A, the liners BB', the spring follower G and the main spring resistance H are of substantially the same construction as the corresponding parts hereinbefore described in connection with Figures 1 to 5, inclusive. The wedge block C has a pair of wedge faces at the inner end thereof designated respectively by 125 and 126, the face 125 being disposed at a relatively een wedge acting angle and the face 126 at a relatively blunt releasing angle with respect to the long'tudinal axis of the mechanism. The wedge block C is cut away at opposite sides as indicated at 50 to present concave recesses adapted to receive convex cylinlilrical enlargements 5151 on the inner sides of the friction shoes E and F; Each friction block 0. The inclined face of the shoe D is designated by 130 and that of the shoe E is designated by 131. Each of the faces 130 and 181 of the shoes isrecessed as indicated at52 and is adapted to receive the face plate F. Each face plate F is of substantially rectangular outline and is ofsuch a thickness as to project inwardly beyond the correspondingly inclined face of the shoe.

The wedge block C is provided with anchoring means comprising a plate-like section. 145 corresponding .to the plate-like section 45 hereinbefore described in connection with the embodiment of the invention illustrated in. Figures 1 to 5, inclusive. The platelike section 1 15 is integrally connected toithe wedge by means of a vertical web 53. As will be evident, outward movement of the wedge is positively limited by engagement of the section14i5 of the anchoring means with the inner ends of the liners B, thereby maintaining the parts of the mechanism assembled.

The spring resistance I-I comprises inner and outer coils in twin arrangement similar to the spring resistance H hereinbefore described, the inner coils extending through openings in the spring follower G and the plate section 145 of the wedge retaining means and bearing on the enlargements of the friction shoes D and E.

In assembling the mechanism, illustrated in Figures 6 and 7, the mode of procedure is substantially the same as that hereinbefore described in connection with the first embodiment of the invention, differing therefrom only in that after the friction shoes have been inserted between the wedge block C and the liners B, the outer ends of the shoes are engaged by pressure means to force the shoes inwardly until the face plates F may be inserted within the recesses 52 provided therefor in the shoes D and E. After the parts have been assembled and the pressure has been removed, the same will assume the normal position illustrated in Figure 7, due to the expansive action of the main spring resistance H, outward movement of the wedge be ng positively limited by the anchoring means 145 thereof and outward movement of the shoes being limited by engagement of the face plates F with the wedge faces of the block C.

The main spring resistance H is preferably placed under initial compression when the parts are assembled so that the shoes will be urged outwardly with respect to the wedge block C, thereby holding the shoes spread apart and producing lateral pressure on the carrying out my invention, the same is merely illustrative, and I contemplate all changes and modifications that come within the scope of the claims appended hereto.

I claim:

1,. In a friction shock absorbing mechanism, the combination with a friction shell; of shoes co operating with the shell; a wedge anchored to the shell, the wedge being limited against outward movement .by said 111- choring means, said wedge block and shoes being .cut away to permit insertion of the shoes within the shell after the wedge has been anchored to the shell; spring resistance means within the shell yieldingly opposing movement of said shoes inwardly of the shell; and detachable face plates mounted on the shoes, said face plates being interposed between the wedge and shoes and enthe wedge to limit movement of the shoes outwardly of the shell.

.2. In a friction shock absorbing mecha nism, the combination with a spring cage having opposed interior liners at the outer end thereof anchored to the cage against movement in a direction lengthwise of the cage, said liners presenting opposed friction surfaces; of friction shoes cooperating with the friction surfaces of the liners; a wedge member interposed between the shoes; spring resistance means within the cage opposing inward movement of the shoes; means rigid with the wedge engaging the inner ends of the liners for anchoring the wedge to the cage and limiting outward movement of the wedge; and means interposed between the wedge and shoes anchored to the shoes and having wedging engagement with the wedge to limit outward movement of the shoes and effect a spreading action of the shoes to hold the liners anchored to the cage.

3. In a,friction shock absorbing mechanism, the combination with a rectangular spring cage; of a pair of liners interlocked with two opposed walls of the cage; a block having inner wedge faces and a rigid extension engaging behind the liners to anchor the wedge to the cage and limit outward movement of the wedge; spring resistance means within the cage; friction shoes co operating with the spring resistance, said shoes being interposed between the wedge and l nersa-nd having frictional engagement with the latter and maintaining the same interlocked with the cage, said shoes being insertible through the open end of the cage after the wedge has been anchored thereto; and means interposed between the shoes and having wedging engagement with the wedge and thereby limiting outward movement of the shoes and holding the same assembled with the cage.

l. In a friction shock absorbing mechanism, the combination with a spring cage provided with detachable liners presenting opposed friction surfaces; of friction shoes oo-operating with the friction surfaces of the liners; a wedge block engaging the shoes; anchoring means for the wedge block; a spring follower bearing on the inner ends of the shoes; twin arranged main spring resistance elements, each twin element comprising an inner and an outer coil spring, the outer coil of which bears directly on the spring follower and the inner coil of which extends through the spring follower and anchoring means, and bears on the corresponding shoe forwardly of the inner end thereof.

5. In a friction shock absorbing mechanism, the combination with a rectangular spring cage; of a pair of liners interlocked with two opposite walls of the cage; a block having inner wedge faces and rigid anchoring means comprising a section of greater width than the distance between the opposed inner surfaces of the liners, thereby engaging behind the same to limit outward movement of the wedge and anchor the same to the cage; spring resistance means within the cage; friction shoes co-operating with the spring resistance, said shoes being disposed between the wedge block and the liners and being insertible through the front end of the cage after the wedge has been assembled with the cage; and face plates interposed between the shoes and the wedge thereby limiting outward movement of the shoes and maintaining the same assembled with the cage.

In witness that I claim the foregoing I have hereunto subscribed my name this 9th day of March, 1927.

JOHN F. OCONNOR. 

